Price label communication system

ABSTRACT

Price label system comprising a price label system server connected to transceivers adapted to communicate price label information to price labels using a communication protocol. A predetermined number of transceivers defines a sub-cell and each sub-cell is associated with a communication profile that defines communication protocols to be used when communicating with the price labels in that sub-cell.

FIELD OF THE INVENTION

The present invention relates to a price label system and a method in aprice label system according to the preambles of the independent claims.

BACKGROUND OF THE INVENTION

The price label system according to the present invention is generallyan electronic pricing and information system that replaces the old paperlabels with electronic labels where the process on labels can bewirelessly changed from a computer.

The actual price changes are not done in the price label system, but inthe store's Price Controlling Application (PCA) system. The PCA containsa database which stores all the information about the items in thestore, e.g. product name, package size, and the current price. Thestore's cash registers are connected to the PCA system, and thus alwayshave the correct price information. The PCA can e.g. be the store'sback-office computer system. There are no limitations regarding hostcomputers for the PCA and the price label system server. They may be runon the same computer or in two (or more) different computers.

The PCA system controls the actual price of an item and provides theprice label system according to the invention with updating informationwhenever the price is hanged. The PCA system interacts with the pricelabel system to supply information to the price labels (PLs). This isnormally performed via a Price File Interface (PFI) that is asoftware-to software interface connecting the PCA system to the pricelabel system server. The only prerequisite is that all PFI files (seebelow) are reachable (can be read and written) within any path of amounted drive or file system known to the computer where the PFI serviceis executing. The transportation mechanisms through the PFI are e.g.common text files, e.g. in 8-bit ASCII format or 2-byte UNICODE. Othertransportation mechanisms are naturally possible. The price label systemautomatically detects the format of the input files. Two PFI files arecreated by the PCA, a message file and a data file.

The price label system creates a third PFI file, a result file that isretrieved by the PCA.

The message file contains one or my commands to the price label, e.g. atarget link command used to establish the connection between an item anda label and an update command used to change the information an thelabel, e.g. the price. The data file contains data such as prices, itemidentity and label identity and the result file contains the resultsfrom executed commands.

The price label system generally comprises software installed in aserver computer, a hardware infrastructure and price labels. Thehardware infrastructure comprises base stations, transceivers andcables. The price labels are mounted with their items in the store, e.g.on the shelf-edges. Transceivers are normally mounted in the ceiling andbase stations normally on a wall. A predetermined number of transceiversare connected to a base station, which is connected to the price labelsystem server, preferably via a hub. The price label server is connectedto the PCA, often via the same network.

FIG. 1 schematically illustrates an overview of the PCA and the pricelabel system briefly described above and in accordance withwell-established technique where the present invention is applicable.

When a price is changed in the PCA system, the information is sent tothe price label system server (PLS server). From the PLS server,designated as “serve” in FIG. 1, the information is sent via a hub andbase stations BS to transceivers in the ceiling where it is transformedinto infrared signals. When the electronic price labels receive theinfrared signals the price is immediately updated.

Each electronic price label acknowledges the updated price bytransmitting a feedback pulse to the transceivers. The feedback pulse isreturned to the server and stored in a database to verify that thetransmission was OK.

Although the system shown in FIG. 1 uses infrared signals whencommunicating with the price label it should be noted that the presentinvention is equally applicable for any type of communication signalused between the price label system and the price labels.

Among different types of communication signal applicable in the systemcan be mentioned radio wave signals, optical signals, electricalsignals.

A cell is defined as the set of transceivers connected to the same basestation. A sub-cell is defined as each set of simultaneouslytransmitting transceivers. All transceivers within a sub-cellsimultaneously transmit the same date. A power supply energizes thetransmitting transceivers.

FIG. 2 illustrates an example of an installation plan with one cellcomprising three sub-cells, SC1, SC2 and SC3, respectively. Eachsub-cell includes a number of transceivers TRX. When configuring cellsand sub-cells many different things must be considered. Among those canbe mentioned that cables to transceivers within one sub-cell must be ofsir lengths in order to minimize phase shifts and that sub-cells shouldoverlap in order to ensure signals of sufficient strengths to alllabels.

A benefit of the sub-cell concept is that it is possible to keep trackof price label locations and that a label that does not respond can bepaged (searched for).

A price label (PL) is an electronic device provided with an LCD displaywith the shape and size of a regular shelf-edge price label. Each PL hasa unique address and is logically connected to a sales item in thestore. Normally the PL displays an item's price. FIG. 3 a shows atypical price label where all fields are active and FIG. 3 b shows aprice label displaying normal price and normal unit price. A sender andtransmitter part 2 and a small solar cell 4 can also be seen on theprice label in FIG. 3 b. A battery, or a combination of battery andsolar cell, provides the power for the PL.

There exists many different kinds of price labels, they can e.g. differin size, in number of price fields or other fields. The word “price” isused throughout the application to define what is displayed on the pricelabel. It should however be noted that although the price label oftendisplays price information it is naturally possible to display othertype of information on the price labels, solely or in addition to priceinformation, without departing from the scope of the present invention.This other type of information may for example be text, figures orimages.

The labels can also differ in the way the price label system needs tohandle them, e.g. with regard to used communication protocol, and if thecircuitry inside the price label has been changed.

The communication between the price label server and a price label isinter alia determined by the value of two parameters: price label family(PL family) and price label family revision (PL family revision).

The PL family is an administrative or logical entity that is used togroup price labels together with similar communication features.

The PL family revision is used to denote minor differences in the valuesof the protocol parameters. A PL family may comprise several PL familyrevisions. To each physical price label is associated a PL type thatencompasses the PL family and the PL family revision.

The communication protocol parameters are collected in protocol objectsin the price label server. In a normally configured price label systemtypically includes a number of such protocol objects to be used whencommunicating with different kinds of price labels.

A protocol object comprises e.g. parameter settings regarding the numberof re-transmissions, re-calibration time, and physical protocolidentity.

When the server is about to communicate with a specific price label itneeds to determine what protocol object to use.

According to a presently used system a specific price label type (withspecific values of family and revision) is mapped to a specificprotocol. FIG. 4 schematically illustrates this. In this case thecommunication between all physical price labels of the same PL type andthe server is always performed in the same way, detained by the protocolobjects settings.

However, in certain situations, e.g. due to environmental circumstances,if the price label is located in a noisy environment or due toconstraints regarding infrastructure components, the used protocol isnot always optimal for a specific situation which sometimes may lowerthe performance of the system.

Constraints regarding infrastructure components may e.g. occur when anew type of transceiver supporting a new IR protocol is introduced. Aphysical FL type may support both the new IR protocol and au older one.Which one to be used is determined by the transceiver type.

The object of the present invention is to achieve a system where anoptimal performance of the system is achieved.

SUMMARY OF THE INVENTION

The above-mentioned object is achieved by a system and a methodaccording to the characterizing parts of the independent claims.

Preferred embodiments are set forth in the dependent claims.

Thus, by using a price label communication profile specially adapted fora specific sub-cell where communication protocol settings are definedbased upon price label types of price labels in that sub-cell and ofdifferent circumstances related to that specific sub-cell, optimalperformance is achieved for the price label system.

The present invention makes it possible to selectively specify protocolsetting for different physical locations in a store (e.g. differentdepartments) and also for different types of infrastructure.

SHORT DESCRIPTION OF THE APPENDED DRAWINGS

FIG. 1 is a schematic illustration of a price controlling applicationsystem and a price label system according to well-established techniquewhere the present invention is applicable.

FIG. 2 illustrates an example of an installation plan for transceivers.

FIGS. 3 a and 3 b shows typical price labels used by the systemaccording to the invention.

FIG. 4 shows communication protocols presently used.

FIG. 5 shows communication protocols according to a preferred embodimentof the invention.

FIG. 6 illustrates an implementation of a preferred embodiment of theinvention.

FIG. 7 shows the main blocks of the price label system according to thepresent invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

FIG. 5 illustrates an example of a preferred embodiment of the inventionwhere two different communication profiles are arranged. The twoprofiles differ in that in profile 1 is “Family PP4C, revision 1” mappedto protocol “PP4B_ProtocolCC” whereas in profile 2 it is mapped toprotocol “PP4C_ProtocolC3”.

When a transmission to a price label is to be performed thecommunication profile for the sub-cell where the price label is locatedis identified. The price label type, comprising inter alia price labelfamily and price label family revision, of the physical price label isthen identified in the profile where it is, together with otherparameters, mapped to a communication protocol applicable for exactlyhis physical price label in this sub-cell.

When assigning a communication profile to a specific sub-cell manydifferent matters must be taken into account. Among those can bementioned environmental circumstances, i.e. if the price label islocated in a noisy environment where reflections and lighting conditionsinterfere with the transmission between the transceivers and pricelabels. Also constraints regarding infrastructure components mayinfluence the choice of communication profile. These differentcircumstances and the PL types of the price labels of that sub-cell areweighted together when determining which communication profile to use ina specific sub-cell.

In a sub-cell having a more disturbed environment the communicationprofile may e.g. be arranged to use a communication protocol where ahigher number of re-transmissions are used compared to a normalsub-cells.

According to a preferred embodiment of the invention is the differentcommunication profiles set up, configured and assigned to sub-cells atrun-time through a system management graphical user interface (GUI) thatis a part of the price label system, or preset at installation time.

FIG. 6 illustrates an implementation of a preferred embodiment of theinvention. Two communication profiles, profile 1 and profile 2, isillustrated. Each communication protocol object, above referred ascommunication protocol, is implemented as an instance of a protocolclass wit properties corresponding to the different communicationparameters.

Each communication profile includes a mapping from price label and otherproperties to a protocol object as illustrated in FIG. 6.

FIG. 7 shows the main blocks of the price label system according to thepresent invention.

The system comprises a price file interface (PF) where data, e.g. newprice of an item, is received in the form of a PFI data file from thestore's PCA-system (not shown in the figure). The received data isstored in an item cache database and a request to create an update jobis generated. A property description file contains item data andinformation how the data should be viewed in a graphical user interface(GUI) in a client (not shown in the figure) connected to the server. Therequest for updating a PL is applied to the “electronic shelf edgelabel” management block (ESL) that handles the connection between itemand price label by accessing item and label information from the itemcache database and also from internal tables in the ESL-block. Todetermine which information to send out to an individual PL, the PL'sassociated PL layout script file is executed based on information in theassociated PL model, using the IPF to select the appropriate layoutscript. The layout script files describe how to map item data onto theprice label. There are a number of layout script files for each PL type.When the layout script is executed, the output from the layout script istransformed into a format called “field data contents” (FDC) containingthe data to send.

The FDCs are collected in a batch in the “price communication service”(PCS) blocks. The PCS block converts, by using “device files” and byusing the settings in an associated communication protocol, the FDC datato frames which are collected into a “device specific data” (DSD) thatin turn is transferred to a sending queue. The “device files” define howto display the data on the label. There is one device file for each PLtype. The PL product representing the physical PL associates the layoutand the PL type.

DSDs from the sending queue are then transmitted to the basestation (BS)and further in the form of data frames via the transceivers& (TRX) sentby IR light to the price labels (PLs).

Below is an overview of the price changing process in a price labelsystem according to a preferred embodiment of the present invention:

-   1. The price label system server from the store's PCA-system    receives a price file containing item number and the new    information, e.g. price.-   2. Look up the item in a database and get the identity of all price    labels (PLs) connected to this item.-   3. Get the PL model to be used. Either as a specified property on    the PL or else use the default model for that PL type. The PL model    contains information about layout scripts to use for different Item    Presentation Forms (see below).-   4. Determine which layout script to use based on the IF for the    item. Item Presentation Form (IPF) is an abstraction of what    information to display on a PL for an Item.-   5. Execute the layout scripts, and perform all the steps needed to    generate the data frame that is to be transmitted to the target PL.-   6. Determine in which sub-cell the PL is located. This could be    either the sub-cell where a price label acknowledge last was    received or the sub-cell initiated by the PCA-system. In this    determined sub-cell the frame containing e.g. price information will    be transmitted.-   7. Fetch the communication settings from the communication protocol    object associated with the determined sub-cell. This is determined    through the communication profile of that sub-cell.-   8. Transmit the frame to a base-station and further to the    transceivers in the determined sub-cell for communication to the    price label(s) using the communication parameters specified in the    protocol object.

The present invention is not limited to the above-described preferredembodiments. Various alternatives, modifications and equivalents may beused. Therefore, the above embodiments should not be taken as limitingthe scope of the invention, which is defined by the appending claims.

1. Price label system comprising: a price label system server connectedto transceivers adapted to communicate price label information to pricelabels using a communication protocol, wherein a predetermined number oftransceivers defines a sub-cell, each sub-cell is associated with acommunication profile that defines communication protocols to be usedwhen communicating with the price labels in that sub-cell, saidcommunication profile is determined by price label categories related toprice labels of that sub-cell and by one or many characteristic(s) ofthat sub-cell, and one of said characteristics is related to theenvironmental conditions for the price labels of that sub-cell.
 2. Pricelabel system according to claim 1, characterized in that one of saidcircumstances is related to constraints regarding infrastructurecomponents.
 3. Price label system according to claim 1, characterized inthat each price label is associated to a price label type.
 4. Pricelabel system according to claim 1, characterized in that saidcommunication profile comprises price label families and price labelfamily revisions.
 5. Price label system according to claim 4,characterized in that a price label family and a price label familyrevision is mapped to a communication protocol.
 6. Method in a pricelabel system according to claim 1, characterized in that the methodcomprises the following steps: initiate a change of informationdisplayed by a price label arranged in a sub-cell, use the communicationprofile associated to that sub-cell and apply the communication protocoldefined by said communication profile when communicating with said pricelabel, wherein said communication profile is determined by price labelcharacteristics related to price labels of that sub-cell and by one ormany circumstance(s) of that sub-cell including at least environmentalconditions.
 7. Price label system according to claim 1, wherein saidenvironmental conditions include reflections and lighting conditions. 8.Method of claim 6, wherein said environmental conditions includereflections and lighting conditions.